It may be worth creating a category for social entrepreneurship which is distinct from the others. But that aside here is a good story in that category.
Room to Read is an organization started by a Microsoft executive who left Microsoft in 2000 to enter the non-profit world and applied the principals of big business to the non-profit world and is attempting to be the Starbucks of libraries in the underdeveloped world. He has a book coming out that should be an interesting read.
There was an interesting paragraph somewhere on his site that made a general observation that I found worth highlighting
What works for one organization may not work for others. But one thing I have found to be missing in the business world is passion. People will work for a while, but once they have financial security, they tend to move away from companies that have invested heavily to recruit and train them. In the social sector, people tend to be much more passionate about the mission, and this helps in retaining top talent. This dedication fuels growth and expansion – and inspires others to be equally committed.
You can buy the book and get the full story – Leaving Microsoft to Change the World .
Another interesting organization is Build